feat: SCC analysis (WIP)

src/eval/mod.rs

@@ -1,12 +1,9 @@
-use std::rc::Rc;
-
 use ecow::EcoVec;
 
 use crate::engine::Engine;
 use crate::env::VmEnv;
 use crate::error::{Error, Result};
-use crate::ir::{self, DynamicAttrPair};
-use crate::ty::common::Const;
+use crate::ir::{self, DynAttr}; use crate::ty::common::Const;
 use crate::ty::internal::{AttrSet, EnvRef, List, ThunkRef, Value};
 use crate::ty::public::Symbol;
 
@@ -32,7 +29,7 @@ impl Evaluate for ir::Attrs {
                 })
                 .collect::<Result<_>>()?,
         );
-        for DynamicAttrPair(k, v) in self.dyns {
+        for DynAttr(k, v) in self.dyns {
             let mut k = k.eval(engine, env)?;
             k.force(engine)?.coerce_to_string();
             attrs.push_attr(k.unwrap_string(), v.eval(engine, env)?);
@@ -315,6 +312,15 @@ impl Evaluate for ir::Thunk {
     }
 }
 
+impl Evaluate for ir::MaybeThunk {
+    fn eval(self, engine: &mut Engine, env: &mut VmEnv) -> Result<Value> {
+        match self {
+            ir::MaybeThunk::Const(cnst) => cnst.eval(engine, env),
+            ir::MaybeThunk::Thunk(thunk) => thunk.eval(engine, env)
+        }
+    }
+}
+
 impl Evaluate for ir::Path {
     fn eval(self, engine: &mut Engine, env: &mut VmEnv) -> Result<Value> {
         todo!()